Summary Air Canada flight 148, a Boeing 747, departed Vancouver, British Columbia, en route to Toronto, Ontario, at flight level(FL)370. Air Canada flight 1155, an Airbus A319, departed Montreal, Quebec, en route to Vancouver at FL390. Both flights were under radar control. The crew of the Boeing 747 requested and was cleared to climb to FL410 approximately 116 nautical miles (nm) west of the Lumsden, Saskatchewan, VOR (very high frequency omni-directional radio range). Approximately 43 nm west of the Lumsden VOR, the crew of the Airbus A319 advised the air traffic controller that there was traffic 5 miles straight ahead and 1000 feet above. The two aircraft passed with zero horizontal and 1100 feet vertical spacing. The required minimum separation was 5 nm horizontally or 2000 feet vertically. Ce rapport est galement disponible en franais. Other Factual Information The Boeing 747 was being controlled by the Lumsden sector controller in the Saskatchewan specialty of Winnipeg Area Control Centre (ACC). When the controller took over the Lumsden sector radar position at about 1604 central daylight time,(1) the Lumsden data position was staffed by the Saskatchewan specialty supervisor. Traffic level was assessed as light, with low complexity, and moderate workload. The staffing in the Saskatchewan specialty met unit standards, and all necessary equipment was serviceable. Based on the traffic level, the supervisor and controller agreed that two controllers were no longer required; therefore, about five minutes after taking over the radar position, the controller also assumed the data position and the supervisor returned to his supervisory duties. It is an accepted and common practice for a controller to work both the radar and data positions simultaneously. Factors considered when deciding if a controller will work both positions are traffic conditions, controller experience and capabilities, controller workload, and available staff. The controller had 29 years' experience, and was qualified for both the radar and data positions. He was on his fourth day of work after two days off. He had been on duty for five hours since the beginning of the shift, and immediately before taking over at the Lumsden sector he had taken a 30 minute rest break. At 1610:47 the crew of the Boeing 747 requested a climb to FL410 from their cruising altitude of FL370. Immediately following the request, the controller issued clearance to climb to FL410 and the Boeing 747 vacated FL370 at 1611:12. At this time the Airbus A319 was still being controlled by the Broadview sector radar controller, and was 128 nm to the east. The two flights were on reciprocal tracks. The Boeing 747 crew initiated the climb in vertical speed mode with 400-500 feet per minute (fpm) selected as a rate of climb. The crew was not required to report their climb rate to the controller, and did not do so. The controller did not issue any instructions with respect to the required climb rate, nor did he instruct the crew to report passing a specific altitude. The data block for each aircraft displayed on the radar indicator module (IM) includes a vertical motion indicator that appears when the aircraft climb or descent rate exceeds 600 fpm. The vertical motion indicator did not appear in the data block for the Boeing 747 at any time during the climb because the climb rate never exceeded the 600 fpm threshold. The IM can be configured to display projected track lines (PTLs) that indicate the extrapolated position of an aircraft at a specified number of minutes in the future. PTLs may be displayed in two modes. In one mode the controller specifies both the desired targets and a time for the length of the track projection; the IM then displays the PTLs until the controller deactivates this mode. In the other mode, PTL ALL, the controller specifies a time for the length of the track projection, and the IM displays PTLs for all targets on the IM for a short time determined by the current setting for the variable system parameter (VSP). The VSP can be set by the data systems coordinator for 0 to 10 seconds, but is normally set at 6 seconds. PTLs are based on current track and ground speed and are updated with each radar scan; therefore, the track projection will change if an aircraft turns or changes speed. Because of these limitations, the controller did not use PTLs to identify traffic conflicts. However, he did use both modes of PTLs a number of times to confirm estimates and control decisions, including a PTL placed on the target of the Boeing 747 at 1612:24 to confirm the estimate for Lumsden. There are additional methods available to highlight conflicts on the IM, such as halos around aircraft targets or range bearing lines connecting aircraft targets; however, there are no standard methods for indicating conflicts on the IM. None of these additional methods were used by the controller. The Air Traffic Control Manual of Operations (ATC MANOPS) specifies the warning indicators to be used on flight progress strips to attract a controller's attention to potentially hazardous or critical situations. The flight progress strip is annotated with a red W in the area that most clearly identifies the reason for the warning. The practice among controllers at the Winnipeg ACC is to use a red W to identify potential conflicts such as aircraft at the same altitude with crossing tracks. Generally they do not use a red W where one aircraft is climbing or descending through the altitude of another aircraft on a reciprocal track. The controller did not use a red W on the flight progress strips for the Boeing 747 or the Airbus A319. ATC MANOPS describes cocking of flight progress strips as an essential control technique used to remind controllers that some further action must be performed, and directs that a strip be cocked when potential situations requiring investigation or further action exist. Winnipeg ACC controllers use this technique to remind them of traffic conflicts such as the one in this occurrence. The controller's normal working practice was to cock a flight progress strip when a climb clearance was issued, and to uncock it immediately when the action of advising the next sector of the revised altitude was complete. When the climb clearance was issued, the flight progress strip for the Boeing 747 had already been cocked to remind the controller that the Lumsden estimate had not yet been passed to the Broadview sector, so he did not need to cock it because of the climb clearance. At 1613:44 he passed the estimate and the altitude of FL410 for the Boeing 747 to the Broadview sector, and Broadview acknowledged. However, the controller could not recall uncocking the flight progress strip at that time, and it could not be determined if the flight progress strip had been uncocked. The controller saw the target for the Boeing 747 climbing through FL380 at 1614:30. He again made the assessment that there was no potential for conflict between the two flights, and did not issue any restrictions or instructions. From 1614:38 until 1615:34 the controller communicated with three other flights, with the Edmonton ACC, and accepted control of Canadian Regional Airlines flight 1458, a Fokker F28 from the underlying Great Plains sector. This flight contacted the Lumsden controller at 1615:27, climbing eastbound through FL290, at which time its radar target was centred longitudinally between the Boeing 747 and the Airbus A319. From 1615:43 to 1618:19, in addition to monitoring the IM, the controller was occupied exchanging data about the Fokker F28 with the Broadview controller, emptying the flight progress strip printer and processing flight progress strips, double-checking estimates, and preparing to pass them to other sectors. All of these tasks are normal controller duties. Interviews with Winnipeg ACC controllers disclosed that non-pertinent flight progress strips were produced. When combining or splitting control sectors, support staff are required to reprogram the computer system to send the flight progress strips to a printer at the appropriate sector. The reprogramming occasionally lags behind the sector reconfigurations. As well, flight progress strips are printed well in advance of the arrival of a flight in a sector. As a result, some flight progress strips are printed at sectors for flights that will not be controlled by that sector. Conversely, a sector may not receive a flight progress strip for a flight that will be controlled by that sector. This requires controllers to perform additional coordination to ensure those controllers that needed the flight progress strip would have it, and also to dispose of non-pertinent flight progress strips. The Lumsden sector had undergone one of these reconfigurations before the occurrence, and the controller was diverting some of his attention to process and discard non-pertinent flight progress strips. There was no information that the controller was missing any pertinent flight progress strips. Quicklook ALL is an IM function that displays full data blocks for all correlated targets currently displayed on the IM. Normally, only aircraft being controlled by that sector display full data blocks, with other targets showing only the controller jurisdiction symbol. Quicklook is activated by pressing a button on the IM control panel, and must be deactivated by a second press of the same button. Quicklook ALL was active on the Lumsden IM at 1614:49 at about the time the controller accepted control of the Fokker F28, and was deactivated at 1616:35. Additionally, at 1616:50 PTL ALL was selected on for all the targets on the Lumsden IM. At 1618:25 the crew of the Airbus A319 reported to the controller that their traffic alert and collision avoidance system (TCAS) indicated traffic 1000 feet above and 5 nm ahead. At the same time, the controller became aware of the traffic conflict on his IM. The two aircraft were 5 nm apart, with the Boeing 747 climbing through FL399. At 1618:32 the controller advised the Airbus A319 that the traffic they had reported was another Air Canada flight, climbing through FL400. At 1618:36 the controller instructed the Boeing 747 to continue the climb without delay. At 1618:39 the Boeing 747 advised the controller that they had the traffic in sight, and that there was no chance of collision. No evasive action was taken by either flight. At 1618:46 the two aircraft passed with zero horizontal and 1100 feet vertical spacing. The TCAS produces advisories to indicate a potential collision threat. The traffic advisory (TA) indicates that the estimated time to the closest point of approach of an intruder aircraft's trajectory is between 35 and 48 seconds, and also that the intruder aircraft will be within 1200 feet but not less than 800 feet relative altitude at the closest point of approach. Both crews received a TA. The Canadian Aviation Regulations (CARs) do not require TCAS to be installed in aircraft flying in Canadian airspace. In 1987, Transport Canada issued Information Bulletin 8709, directing managers to brief controllers about the proper use of strip-cocking techniques to prevent operating irregularities. In 1992, Safety Bulletin 9201 emphasized the need for complete attention to detail to prevent loss of separation between aircraft climbing on reciprocal tracks while under radar control. In 1995, Safety Bulletin 9501 recommended the use of procedural reminders to alert controllers to the need to monitor closely aircraft on reciprocal tracks. It recommended the use of restrictions such as track or heading changes to ensure separation was maintained. In 1999, Nav Canada issued ATC Information Bulletin 1999-2, describing the capabilities of conflict alert software. In 2000, Nav Canada issued Safety Bulletin 2000-1, emphasizing the need for controllers to closely monitor aircraft separation to confirm the accuracy of their expectations of aircraft performance, and to take alternative action if their expectations are proven to be incorrect. The original performance specifications for the ATC radar data processing system (RDPS) software included provisions for aircraft conflict alerts. During testing in the late 1980s and early 1990s, the RDPS conflict alert function was found to have several faults and was not considered acceptable for operational use. This function was still not operational at the time of this occurrence. In the investigation report on occurrence A99H0001, involving a loss of separation between two Boeing 767 aircraft west of Langruth, Manitoba, the TSB made a recommendation for the consideration of both Nav Canada and Transport Canada that: Nav Canada commit, with a set date, to the installation and operation of an automated conflict prediction and alerting system at the nation's air traffic control facilities to reduce the risk of a midair collision. Nav Canada responded that testing of conflict alert software was underway. A national release of the software is planned following completion of testing and development.